# Octave 常用函数
```m
A=bitshift(A，k) % 返回移位了 k 位的 A 的值。当 K>0 时左移，当 k<0 时右移。
seconds=time() % Return the current time as the number of seconds since the epoch.
t=now() % Return the current local date/time as a serial day number (see datenum).
% 绘制 3D 散点图 plot3(x, y, z)
plot3([0,242.5,242.5,0,0,242.5,242.5,0],[45,45,21,21,9,9,9,9],[0,0,0,0,-9,-9,44.5,44.5],'x')
```
